Self-aligning idler for belt conveyers



Sept. 23, 1941. R. w. PARKER 2,256,685

SELF-ALIGNING IDLER FOR BELT CONVEYERS Original Filed Oct. 7, 1958 V 2Sheets-Sheet 1 m fwd/W Sept. 23, 1941. R. w. PARKER 2,256,685

I SELF-ALIGNING IDLER FOR BELT 'CONVEYERS Original Filed Oct. 7, 1938 2 Sheets-Sheet 2 :24 ll 29 w m? W A Ill l Qvwwwtom fibiari/[Pmfar Patented Sept. 23, 1941 SELF-ALIGNING IDLER FOR BELT CONVEYERS Richard W. Parker, Indianapolis, Ind., assignor to Link-Belt Company, a corporation of Illinois Original application October 7, 1938, Serial No.

233,847, now Patent N 0. 2,225,276, dated December 17, 1940. Divided and this application November 25, 1939, Serial N 0. 306,169

Claims.

This invention relates to new and useful improvements in self-aligning idlers for belt conveyers. This application is a division of my copending application which maturedinto Patent No. 2,225,276 on December 17, 1940.

It is extremely difiicult to maintain the belts of belt conveyers running in proper alignment with respect to the fixed carrying idlers employed for supporting the active and inactive runs of the belt. Such misalignment, of course, may result from any one or more of several different causes; such as improper transverse loading of the belt, improper alignment of the several fixed carrying idlers, uneven longitudinal stretching and shrinking of the opposite edge portions of belts carrying wet loads, such as sand and gravel, due to uneven transverse drying during inactive periods, and the like. This problem of alignment is encountered with both theactive and inactive runs of flat belt conveyors and the fiat return or inactive run of troughed belt conveyers. As the roll or rolls of the idlers embodying this invention are shaped and arranged to take care of flat runs, either active or inactive, of belt conveyers, this invention is particularly concerned with realignment of such runs.

It is the present practice to employ some form of mechanism which will operate automatically, in response to misaligmnent of a belt, to train the belt back into a normal transverse position. Most of such devices consist of self-aligning idlers substituted for certain of the fixed carrying idlersof a belt conveyer. Each of these selfaligning idlers includes an idler frame supported for rotating or swiveling movement about the axisof a vertically arranged gudgeon. Movementof the idler frame to effecttraining of the belt is accomplished by means of some forcedeveloping instrumentality which is added to and operatively associated with the idler frame or the roll or rolls carried thereby. .Theseinstrumentalities usually take the form of small guiding or actuating rolls against which the belt edges bear and with the said rolls arranged relative to the idler frame so that engagement of one of the rolls by an edge of a misaligned belt will cause the idler frame to move to trainthe belt back into its proper position; brake shoes which drag on the beltor idler rolls and thereby cause proper swinging movement of the idler frame, or counter-weighted members rotatably carried by the idler frame and functioning to develop inertia when they are rotated as a result of engagement with the belt. Such selfaligning idlers naturally costmore thanthe conventional fixed carrying idlers and usually require more space to accommodate the force-developing instrumentalities.

It is the primary object of this invention .to provide self-aligning idlers for belt conveyers, of both fiat and troughed belt type and more specifically for the active and inactive runs of fiat belts and the inactive runs of troughed belts, whose construction is much simpler, more compact, and less expensive than the self-aligning idlers now in common use.

' A furtherimportant object of the. invention is to provideself-aligm'ng idlers which possess the aforementioned advantages primarily because of the fact that they do not require the addition of force-developing instrumentalities to rotate the .idler frames to bring about the desired belt training movement of the frames.

A still further object of the invention'is'to pro- .vide a self-aligning idler of the rotatable frame .type in which the frame is supported for movement in such a manner that misalignment of a belt relative thereto will produce an unbalanced weight condition which will supply-the iorcerequired to effect the necessary belt training movement of the idler frame.

Another object of the invention is .to provide a self-aligning idler in which the various ele ments are so arranged as to reduce the over all depth of the idler, which in many installations is a great advantage.

Another object of the invention is to provide a self-aligning idler for flatbelts, in either active or inactive runs, which will not damage the belt edge as aresult of contact with a force-developing instrumentali-ty.

Other objects and advantages of theinvention will be apparent during the course of the following description.

In the accompanying drawings forming a part of this specification and in which like numerals are employed to designate like parts throughout thesame,

Figure 1 is an elevational-view of a self-aligningidler embodying this invention,

Figure 2 is a top plan view of the idler structure disclosed in Fig. l,

Figure 3 is avertical sectional-view taken on line 3-3 of Fig. l,

Figure 4 is an elevational View of a modified formof self aligning idler embodying this invention,

Figure 5 is a top plan view of the self-align. ing idler structure disclosed in -Fig. 4, and

illustration are shown the preferred embodiments of this invention, and particularly. referring to Figs. 1 to 3, inclusive, there is disclosed a self-aligning idler structure'which is intended for use in training load carrying runs of flat belts or inactive runs of either flat or troughed belts.

7 its rolls I9 become unbalanced and are caused to swivel about the axis of the gudgeon. One of In these figures, the reference character] designates a channelbase to the opposite ends ff whichattaching brackets 8 are welded. These return or inactive run of a belt, 2| resting on the rolls 59. Due to th positioning of the roll shaft I8 above the gudgeon 26 and laterally of the gudgeon axis, the roll axes will be permitted to movein an arc or a plane which is inclined or arranged at right angles to the axis of the brackets are employed to attach the bas'elto 'the I stringers of a belt conveyer, not shown: This channel base is arranged with its top surface extending trulyhorizontally, Rivetedgto the;

centerof the channel base is abearingfbracket" 9 provided with the bearing sleeve I6 at its upper end; Fig. l'clearly discloses the fact that the axis of this bearing sleeve I6 is inclined. 1

Arectangularly shapedidler frame II is provided andiisformed of longitudinally extending side bars 12 which are interconnected at their opposite. ends by vmeans of end brackets I3; Theseends brackets are suitably .welded to the side bars; I2... At the central portion of the idler which are spaced at their adjacent ends and are arranged. in axial alignment with each other. For-the purpose of retaining the two bearing brackets M in their desired spaced, aligned positions,'bracket arms I! are provided and are ar-,- ranged .asis best illustrated in Figs. 2. and 3. The four bracketsl3 and I1 may be considered as being arranged in two pairs with each pair functioning to support. the shaft 18 of anidler roll I9.., .These two idler; rolls I9, therefore, are spaced at theiradjacent ends to. accommodate the bracket members I1 and the bearing sleeves I6. A, gudgeonlfilis received within the bearing sleevesIll-and, I6 for pivotally connecting the idlerfrarne and its rolls to the'bracket 9. As is clearly illustratedin Fig. .3, the axis. of the gu'dgeon-Zfl is inclined. .Due to theprovision of the two rolls i9 whichare axially spaced and the arrangement of thebearing sleeves I6.in the space between these two. rolls, theoverall height of the entire self-aligning idler structure is reduced- I V The-structure of. Figs. 1 to 3, inclusive, may be assembled as follows. The gudgeon 20 first may beattached to the. bearing sleeve I6 of the bracket 9. With the gudgeon positioned in this manner,,the lower bearing sleeve I6 may be applied to the lower end of the gudgeon with the bracket arms I! attached, as by welding, to the be'Iapplied to the upperend of the gudgeon and suitably attached, as by welding, to the bracket arms I1. 'One of the longitudinally extending sidebars I2, with the end brackets 13 weldedv thereto, then may be'fitted in the channel of its Y end portion I5.

Thefinal step in the assembly consists of positioning the remaining longitudinallyextendingside bar I2 in its channel of the 7 end portion I5 and Welding the ends of this last T-shaped idler frame 36.

side bar I2 to'the end brackets I3. The four end 'bracket'sjIS and l'! are then positioned in readiness'to receive the shafts I8 of the'two idler roJlal9..

gudgeon and positioned to intersect the gudgeon When the belt ZI moves out aligning idler structure, the idler frame II and the-rolls -ls and the cooperating portion of the idler frame will dip downwardly and forwardlywhilethe remaining roll and its portion of the idler frame. will move upwardly and rearwardly.

Due to the positioning of the rolls I9 above the gudgeon and between the ends of the same, the load'imposed upon the rolls by the belt and its load will be applied radially to the bearing sleeves IQ and I6. a

The form of self-aligning idler disclosed in j Figsi' l to 6, inclusive, which is intended for use in. training a'fiat belt, in either an activeor an inactive run, includes a channelbase 22 tothe opposite ends of which are welded the attaching brackets :23. These attachingbrackets are-intended to mount the idler upon the stringers of a belt conveyer frame, not shown. The attache ing brackets support the channel base 22 plane of thestringers. a a A- pair of bearing brackets 24 is 'provide'd and these brackets are interconnected by'the securing elements 25 which maytake the form ofbolts and nuts. These elements interconnectthe two bearing brackets 24 so that their bearing sleeves or sockets 26 will bejarranged in spaced, .axial alignment. .To fasten the bearing brackets to the center of the top of the channel base 22, rivets 21 are employed. It'will be notedthatthe aligned bearing cups or sleeves 26 have their common axis inclined. A gudgeon 28 is mounted in the bearing openings of the'sleeves 26 and has attached to the portion of the same arranged between the bearing sleeves 26 a' bearing bracket 29 which isattached to the middle .portion of a This idler frame has attached to the same the upstanding arms 3i which function to rotatably support the idler roll 32 by meansof its shaft 33; Fig. 6 clearly discloses'the fact that the gudgeon 28 is supportedwith its axis inclined. The idler frame 36 with its roll 32 is centrally attached to the gudgeon 28 for swinging movement about the inclined axis of this gudgeon- The idler frame 30 and its roll, therefore, will move through 'an arcuate path or a plane which is inclined and which intersects the gudgeon between its ends; As theroll 32 is located above'the'gudgeon and is attached to the latter ata point. intermediate its ends, anyload applied to the roll 32 will. be delivered radially to the' bearing cups 26 and the bearing bracket 29. gThe laterallyspaced ar-' rangement of the'rollshaft 33 with respect to the gudgeon will cause the roll to partake of a caster movement with respect to theaxis of the gudgeon. v v p When a belt ridingon the roll 32 becomesmis! aligned, the roll and its framewill'become fin-g balanced and one side of the roll and frame will dip downwardly and forwardlywhile the remaining side of the roll and frame will move upwardly and rearwardly. This swiveling movement of the roll willretain'ormove the belt back into its normal transverse position." 1

in the Considering thetwo different forms of selfaligning idlers, it willbe seen that each one possesses an idler frame which carries one or.

more idler rolls with the frame and rolls pare taking of pivotal movement about the axis of a gudgeon which is inclined at an angle lying between the perpendicular and the horizontal. This angle of inclination should be from 20 to 50 to obtain the best results. The devices employed for connecting the idler roll or idler rolls to the gudgeon are so constructed and arranged in each idler structure as to position the roll or rolls, or at least their axes, laterally of any vertical plane passing through the supporting base and laterally of the axis of rotation of the supporting gudgeon. The rolls, therefore, partake of the movement of a caster Wheel about the gudgeon axis. This caster movement is modified by the inclination of the gudgeon axis so that pivotal movement of the idler frame and its roll or rolls causes one side of the movable elements to dip downwardly and forwardly with respect to the direction of travel of the conveyer belt, which direction is indicated by arrows in the several figures, while the remaining side of the movable structure moves upwardly and rearwardly. Although plane bearings, gudgeons, and the like, have been shown for the various pivot points, it will be understood that anti-friction and other types of bearings can be employed without modifying the invention.

It is to be understood that the forms of this invention herewith shown and described are to be taken as preferred examples of the same, and that various changes in the shape, size, and arrangement of parts may be resorted to without departing from the spirit of the invention or the scope of the subjoined claims.

Having thus described the invention, I claim:

1. A self-aligning idler for belt conveyers comprising a roll for flatly supporting the width of a belt run with the roll being arranged normally in parallelism with the plane of the flat belt, an idler frame for carrying the roll, a tubular bracket attached to the central portion of the idler frame and arranged so that a plane containing the roll axis and normal to the tubular bracket axis will bisect said bracket, a gudgeon secured in the bore of the tubular bracket and projecting equal distances therefrom at its opposite ends, a pair of bearing members each having a bearing cup to freely rotatably receive and completely enclose a projecting end of the gudgeon, said bear. ing members being relatively shaped and arranged to support the gudgeon at an inclination to the path of travel of and in the direction of departure of the belt so that the aforesaid plane will be inclined to the path of travel of and in the direction of approach of the belt, and means for supporting said pair of bearing members.

2. A self-aligning idler for belt conveyers, comprising a bracket, an idler frame, idler roll means mounted on the idler frame, and a gudgeon, said bracket having means for supporting the gudgeon with its axis inclined to the plane of travel of the belt, said idler frame having means for mounting it on the gudgeon for swinging movement about the axis of the gudgeon, the axis of the idler roll means, during swinging movement of the idler frame, traveling in an inclined plane which is normal to the axis of the gudgeon and which bisects the gudgeon substantially at its longitudinal center, the means of said bracket and the means of said idler frame comprising three cylindrical sections which collectively enat'their outer ends to cover the end faces of thegudgeon' and'thereby' complete the enclosing of the gudgeon.

3. A self-aligning idler for belt conveyers, com

prising a bracket, an idler frame, idler roll means including a pair of axially spaced aligned rolls journaled in the idler frame, and a gudgeon, said bracket having means for supporting the gudgeon with its axis inclined to the plane of travel of the belt, said idler frame having means for mounting it on the gudgeon for swinging movement about the axis of the gudgeon and with the gudgeon lying opposite to the space between the adjacent ends of the rolls, the axis of the idler roll means, during swinging movement of the idler frame, traveling in an inclined plane which is normal tothe axis of the gudgeon and which bisects the gudgeon substantially at its longitudia nal center, the means of said bracket and the means of said idler frame comprising three cylindrical sections which collectively enclose the entire length of the gudgeon, the intermediate one of said three sections being arranged to be bisected by the aforesaid plane of travel of the idler roll means axis and being attached to the gudgeon, the two end sections being closed at their outer ends to cover the end faces of the gudgeon and thereby complete the enclosing of the gudgeon.

4. A self -aligning idler for belt conveyers, comprising a vbracket, a rectangular idler frame including two pairs of roll supporting members, idler roll means including a pair of axially aligned rolls journaled in the two pairs of supporting members of the idler frame, and a gudgeon, said bracket having means for supporting the gudgeon with its axis inclined to the plane of travel of the belt, said idler frame having means for mounting it on the gudgeon for swinging movement about the axis of the gudgeon and with the gudgeon lying opposite to the space between the adjacent ends of the rolls, the axis of the idler roll means, during swinging movement of the idler frame, traveling in an inclined plane which is normal to the axis of the gudgeon and which bisects the gudgeon substantially at its longitudinal center, the means of said bracket and the means of said idler frame comprising three cylindrical sections which collectively enclose the entire length of the gudgeon, the intermediate one of said three sections being arranged to be bisected by the aforesaid plane of travel of the idler roll means axis and being attached to the gudgeon, the two end sections being closed at their outer ends to cover the end faces of the gudgeon and thereby complete the enclosing of the gudgeon.

5. A self-aligning idler for belt conveyers, comprising a bracket, a rectangular idler frame including two pairs of roll supporting membersarranged to define two roll receiving spaces which are separated from each other at their adjacent ends, idler roll means including a pair of rolls journaled in the two pairs of supporting members so as to occupy the said roll receiving spaces, and a gudgeon, said bracket having means for supporting the gudgeon with its axis inclined to the plane of travel of the belt, said idler roll having means for mounting it on the gudgeon for swinging movement about the axis of the glidgbn an which bise'tits, ,thlgudfeon substanhe t rmed a nwfa tvhm -s q msb ifi atgachedt6 the gudeori', the two end. .sectiqng f being fclose dvattheir mite; (ends to bovrftheild:

faces of 'theQudoriand thereby cqmiqletqJhe 

